U.S. patent number 9,668,746 [Application Number 13/937,799] was granted by the patent office on 2017-06-06 for adjustable allograft templates and methods of use.
This patent grant is currently assigned to Allotemplate, LLC. The grantee listed for this patent is Jordan P. Grossman, Michael S. Lee, James Rohl, Shannon M. Rush. Invention is credited to Jordan P. Grossman, Michael S. Lee, James Rohl, Shannon M. Rush.
United States Patent |
9,668,746 |
Lee , et al. |
June 6, 2017 |
Adjustable allograft templates and methods of use
Abstract
Adjustable allograft templates and methods of use are disclosed
where a template for resecting a tissue region may generally
comprise a template frame having a surface for contacting the
tissue region and which defines an open area of tissue to be
resected. A frame assembly along the template frame may be
translatable relative to the template to adjust a size of the open
area of tissue to be resected. One or more inner guidance slots may
be defined along the frame such that the inner guidance slots are
spaced relative to one another to define the tissue within the open
area to be resected from a patient. Additionally, one or more outer
guidance slots may also be defined along the frame and aligned
adjacent to the inner guidance slots. The outer guidance slots may
be spaced relative to one another to define the tissue to be
resected from a donor.
Inventors: |
Lee; Michael S. (Grimes,
IA), Rush; Shannon M. (Pleasanton, CA), Grossman; Jordan
P. (Cuyahoga Falls, OH), Rohl; James (Prescott, WI) |
Applicant: |
Name |
City |
State |
Country |
Type |
Lee; Michael S.
Rush; Shannon M.
Grossman; Jordan P.
Rohl; James |
Grimes
Pleasanton
Cuyahoga Falls
Prescott |
IA
CA
OH
WI |
US
US
US
US |
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Assignee: |
Allotemplate, LLC (Grimes,
IA)
|
Family
ID: |
51208288 |
Appl.
No.: |
13/937,799 |
Filed: |
July 9, 2013 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20140207144 A1 |
Jul 24, 2014 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13789356 |
Mar 7, 2013 |
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61756214 |
Jan 24, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B
17/142 (20161101); A61B 17/154 (20130101); A61B
17/15 (20130101); A61B 2090/3937 (20160201); A61B
2090/062 (20160201); A61F 2002/4649 (20130101); A61B
2090/034 (20160201); A61F 2/4202 (20130101) |
Current International
Class: |
A61B
17/15 (20060101); A61B 17/14 (20060101); A61B
90/00 (20160101); A61F 2/46 (20060101); A61F
2/42 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lawson; Matthew
Assistant Examiner: Sipp; Amy
Attorney, Agent or Firm: Davis, Brown, Koehn, Shors &
Roberts, P.C. Solberg; Sean D.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser.
No. 13/789,356 filed Mar. 7, 2013, which claims the benefit of
priority to U.S. Prov. App. 61/756,214 filed Jan. 24, 2013, each of
which is incorporated herein by reference in its entirety.
Claims
What is claimed is:
1. A template for resecting a tissue region, comprising: (a) a
template assembly having a curved surface for contacting the tissue
region; (b) a frame assembly comprising: (i) first and second inner
guidance slots defined along the frame assembly, wherein the first
and second inner guidance slots are spaced relative to one another
to define a width of tissue to be resected from a patient; (ii) a
third inner guidance slot defined along the frame assembly, wherein
a length of the third inner guidance slot is perpendicular to a
length of each of the first and second inner guidance slots and
wherein the third inner guidance slot defines a length of the
tissue to be resected from the patient; (iii) first and second
outer guidance slots defined along the frame assembly and aligned
adjacent to the first and second inner guidance slots, wherein the
first and second outer guidance slots are positioned closer to an
outer edge of the frame assembly in relation to the first and
second inner guidance slots, wherein the first and second outer
guidance slots are spaced relative to one another to define a width
of tissue to be resected from a donor, wherein the width of tissue
to be resected from the donor is greater than the width of tissue
to be resected from the patient; and (iv) a third outer guidance
slot defined along the frame assembly and aligned adjacent to the
third inner guidance slot, wherein the third outer guidance slot is
positioned closer to the outer edge of the frame assembly in
relation to the third inner guidance slot, wherein a length of the
third outer guidance slot is perpendicular to a length of each of
the first and second outer guidance slots and wherein the third
outer guidance slot defines a length of the tissue to be resected
from the donor, wherein the frame assembly is translatable relative
to the template assembly.
2. The template of claim 1, wherein the frame assembly comprises a
first portion which lies along a first plane and a second curved
portion which extends and curves in an arcuate manner away from the
first portion along a second plane.
3. The template of claim 1 wherein the first, second, and third
outer guidance slots are formed at an angle relative to the first,
second, and third inner guidance slots along the frame.
4. The template of claim 3 wherein the angle of the first, second,
and third outer guidance slots is 2.5 degrees relative to the
first, second, and third inner guidance slots.
5. The template of claim 1 wherein a shape of the frame assembly is
variable according to a shape of the tissue to be resected.
6. The template of claim 1 further comprising one or more saws
which are insertable through the first, second, and third inner
guidance slots and the first, second, and third outer guidance
slots.
7. The template of claim 1 wherein the frame assembly defines one
or more openings sized for a securement wire or pin.
8. The template of claim 7 further comprising one or more
securement wires or pins for insertion through the one or more
openings.
9. A template for resecting a tissue region, comprising: (a) two
channels defined in a template assembly; (b) a curved contact
surface defined in the template assembly; and (c) a frame assembly
slidably positioned within the two channels, the frame assembly
comprising: (i) first, second, and third inner guidance slots
defined in the frame assembly, wherein a length of the third inner
guidance slot is perpendicular to a length of each of the first and
second inner guidance slots, and wherein the first, second, and
third inner guidance slots are defined in the frame assembly in
relation to each other so as to define an area of tissue to be
resected from a patient; and (ii) first, second, and third outer
guidance slots defined in the frame assembly substantially adjacent
to the first, second, and third inner guidance slots, respectively,
wherein a length of the third outer guidance slot is perpendicular
to a length of each of the first and second outer guidance slots,
wherein the first, second, and third outer guidance slots are
positioned closer to and substantially adjacent to an outer edge of
the frame assembly in relation to the first, second, and third
inner guidance slots, and wherein the first, second, and third
outer guidance slots are defined in the frame assembly in relation
to each other so as to define an area of tissue to be resected from
a donor, wherein the frame assembly is slidable in relation to the
template assembly such that a size of the area of tissue to be
resected from the patient and a size of the area of tissue to be
resected from the donor is adjustable.
10. The template of claim 9, wherein the size of the area of tissue
to be resected from the donor is larger than the size of the area
of tissue to be resected from the patient.
11. The template of claim 9, further comprising a fourth inner
guidance slot defined in the template assembly.
12. The template of claim 11, further comprising a fourth outer
guidance slot defined in the template assembly, wherein the fourth
outer guidance slot is substantially adjacent to the fourth inner
guidance slot.
13. The template assembly of claim 12, wherein a length of the
fourth outer guidance slot is perpendicular to the length of each
of the first and second outer guidance slots.
14. The template assembly of claim 12, wherein the first, second,
third, and fourth outer guidance slots define the area of tissue to
be resected from the donor.
15. The template assembly of claim 11, wherein a length of the
fourth inner guidance slot is perpendicular to the length of each
of the first and second inner guidance slots.
16. The template assembly of claim 11, wherein the first, second,
third, and fourth inner guidance slots define the area of tissue to
be resected from the patient.
17. A template for resecting tissue, the assembly comprising: (a)
first and second channels defined in a template assembly; (b) a
contact surface defined on a distal portion of the template
assembly, the contact surface comprising a predefined concave
curvature; (c) a frame assembly slidably disposed within the first
and second channels; (d) first, second, and third inner guidance
slots defined in the frame assembly, wherein a length of the third
inner guidance slot is perpendicular to a length of each of the
first and second inner guidance slots; (e) a fourth inner guidance
slot defined in the template assembly, wherein a length of the
fourth inner guidance slot is perpendicular to the length of each
of the first and second inner guidance slots; (f) first, second,
and third outer guidance slots defined in the frame assembly,
wherein a length of the third outer guidance slot is perpendicular
to a length of each of the first and second outer guidance slots;
(g) a fourth outer guidance slot defined in the template assembly,
wherein a length of the fourth outer guidance slot is perpendicular
to the length of each of the first and second outer guidance slots;
wherein the first, second, third, and fourth inner guidance slots
define an area of tissue to be resected from a patient, wherein the
first, second, third, and fourth outer guidance slots define an
area of tissue to be resected from a donor, wherein the frame
assembly is slidable in relation to the template assembly such that
a size of the area of tissue to be resected from the patient and a
size of the area of tissue to be resected from the donor are
adjustable.
18. The template assembly of claim 17, wherein the first, second,
and third outer guidance slots are disposed closer to an outer edge
of the frame assembly than the first, second, and third inner
guidance slots.
19. The template assembly of claim 17, wherein the size of the area
of tissue to be resected from the donor is larger than the size of
the area of tissue to be resected from the patient.
20. A template for resecting a tissue region, comprising: (a) a
template assembly having a surface for contacting a naturally
occurring tissue region; (b) a frame assembly comprising: (i) first
and second inner guidance slots defined along the frame assembly,
wherein the first and second inner guidance slots are spaced
relative to one another to define a width of tissue to be resected
from a patient; (ii) a third inner guidance slot defined along the
frame assembly, wherein a length of the third inner guidance slot
is perpendicular to a length of each of the first and second inner
guidance slots and wherein the third inner guidance slot defines a
length of the tissue to be resected from the patient; (iii) first
and second outer guidance slots defined along the frame assembly
and aligned adjacent to the first and second inner guidance slots,
wherein the first and second outer guidance slots are positioned
closer to an outer edge of the frame assembly in relation to the
first and second inner guidance slots, wherein the first and second
outer guidance slots are spaced relative to one another to define a
width of tissue to be resected from a donor, wherein the width of
tissue to be resected from the donor is greater than the width of
tissue to be resected from the patient; and (iv) a third outer
guidance slot defined along the frame assembly and aligned adjacent
to the third inner guidance slot, wherein the third outer guidance
slot is positioned closer to the outer edge of the frame assembly
in relation to the third inner guidance slot, wherein a length of
the third outer guidance slot is perpendicular to a length of each
of the first and second outer guidance slots and wherein the third
outer guidance slot defines a length of the tissue to be resected
from the donor, wherein the frame assembly is translatable relative
to the template assembly.
Description
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for
resecting allogeneic grafts and implanting them in a controlled
manner. More particularly, the present invention relates to methods
and apparatus for resecting allogeneic grafts and implanting them
in a patient in a controlled manner through use of an allograft
template.
BACKGROUND OF THE INVENTION
An osteochondral lesion (osteochondritis dissecans or OCD) is an
injury or small fracture of the cartilage surface of the talus
which typically occurs via a crush or injury to the surface of the
bone during the abnormal motion of the ankle in a sprain. The OCD
sits on the medial or lateral shoulder of the talar dome and is
situated on the top and the side of the joint surface. The talus
bone is part of the collection of bones which forms the lower part
of the ankle joint.
With an inversion or eversion stress on the ankle, the talus and
tibia and/or fibula will contact each other with massive stress,
resulting in a compression or shear stress on the surface of the
talus and underlying injury.
In an ankle allograft replacement, an entirely new joint surface
(made of bone and cartilage harvested from a fresh cadaver) is
typically implanted instead of replacing the ankle joint with a
replacement made of metal and plastic. The operation involves
removal of a segment of bone and cartilage from the recipient ankle
and identical bone cuts made on the ankle cadaver graft.
A cutting jig is typically used to harvest the ankle joint from the
cadaver ankle. The block is fixed on to the cadaver (e.g., using
one or more K-wires) and the cuts are made to remove the ankle
joint which is then implanted into the recipient. Properly fitting
a donor bone section into the resection site for a patient is
important for recovery time, longevity, and performance for the
patient.
However, such cutting jigs are time-consuming to set up and use and
may not enable enough of a precise cut for providing a bone graft
suitable for resection and implantation. Such an ill-fitting graft
may subsequently increase the time for bone in-growth and patient
recovery time. Moreover, part of the imprecise cuts may occur
because of improper offsetting of the jigs in failing to account
for kerf losses incurred when cutting into the bone due to the saw
or blade.
Accordingly, there exists a need for methods and apparatus which
facilitate procedures such as calcaneal osteotomy procedures by
providing for easier and more accurate blade positioning and
adjustment features and which provide for shorter procedure
times.
SUMMARY OF THE INVENTION
An allograft template may be used as a cutting jig which allows for
en bloc resection and grafting of bone between a donor and a
patient. The template may be sized in various configurations such
that the template may be used for resection and grafting along
various regions of the body. Hence, while one particular
application for the template may be for resection and grafting to
correct for osteochondral lesions along the talus bone, the
template may be used in various alternative orthopedic
procedures.
The allograft template may facilitate guidance of the saw to allow
for resection of a donor graft in a size which is slightly larger
than the portion of bone to be resected from the patient bone.
Because the same template may be used between the donor and the
patient, the cuts may be maintained in a consistent manner between
the resection sites. The cuts may be formed in a parallel or angled
manner depending upon the angling of the guidance slots defined
along the template. Moreover, by accounting for kerf losses in the
bone due to the saw cuts, the resection sizes may be offset
accordingly by the template. The resulting donor graft may be
implanted in the patient resection site resulting in a press-fit
which backfills the patient resection site and ensures a secure
graft. Hence, the allograft template reduces errors in forming a
resection site in the bone of the patient and further reduces
errors (e.g., errors resulting from thickness of the blade,
measurement errors, cutting errors, etc.) in the forming and
extraction of the graft from the bone of the donor.
Generally, a template for resecting a tissue region may comprise a
template frame having a surface for contacting the tissue region
and which defines an open area of tissue to be resected, one or
more inner guidance slots defined along the frame, where the inner
guidance slots are spaced relative to one another to define the
tissue within the open area to be resected from a patient, and one
or more outer guidance slots defined along the frame and aligned
adjacent to the inner guidance slots, where the outer guidance
slots are spaced relative to one another to define the tissue to be
resected from a donor.
One example of a method of resecting the tissue region may
generally comprise securing the template frame upon a first tissue
region to be resected, where the frame defines an open area of the
first tissue to be resected, resecting the first tissue by cutting
along one or more inner guidance slots defined along the frame,
removing the template frame from the first tissue region, securing
the template frame upon a second tissue region to be resected,
where the frame defines the open area of the second tissue to be
resected, and resecting the second tissue by cutting along one or
more outer guidance slots defined along the frame.
In one variation of an allograft template assembly, the template
may generally comprises a first portion of a frame which may lie
along a first plane and a second curved portion which may extend or
curve in an arcuate manner away from the frame along a second
plane. The frame and curved portion may together form a framed
opening which defines the border or framed boundary of the bone
portion to be either grafted and/or resected. Moreover, the frame
and curved portion may define one or more frame guidance slots and
guidance slots along the template assembly for defining the tissue
area to be cut and for guiding the saw and/or blade along the
tissue, as described in further detail below.
Additionally, the frame and/or curved portion may incorporate a
cross member extending between the frame members for providing
structural support and stability and also for optionally providing
one or more cross member openings through which pins or wires may
be passed for securement to the underlying tissue or bone, such as
the bone to be resected from a patient. To facilitate handling of
the template assembly during a grafting and/or resection procedure,
one or more handles may be attached, for instance, along the cross
member to extend from the template assembly. Handles may be
positioned along other sections of the template assembly if so
desired.
One or more supporting flanges may also be optionally integrated to
extend outwardly along one or both sides of the frame and/or curved
portion. These supporting flanges may define one or more flange
openings defined at various angles therethrough. Pins or wires may
be passed through these flange openings for securement to the
underlying tissue or bone, such as the bone of the donor at regions
adjacent to the resected bone.
The frame and curved portion may define an inner guidance slot
defined along the length and an additional outer guidance slot may
also be defined along the length of the frame and part of curved
portion in parallel with the inner guidance slot. With the inner
and outer guidance slots defined parallel to one, the saw or blades
may be inserted through or along a respective guidance slot such
that the saw or blade become transversely oriented relative to the
inner guidance slot and outer guidance slot.
In use, the template assembly may be used to resect a portion of
bone from the bone of the donor which is slightly larger than the
corresponding resected opening in the bone of the patient. Hence,
the resulting resected bone segment from the donor may result in a
graft which can be press-fit into the patient's bone. By accounting
for the kerf loss in the bone or tissue typically due to the width
of the saw or blade passing through bone or tissue, the width of
the resected bone portion may be sized in a consistent and
repeatable manner. The opposed inner guidance slots may be
separated from one another to have a width of the patient's bone
plus the kerf loss to be equal to the width of the donor's bone
minus the kerf loss. Hence, the inner guidance slots may define the
width of the resected bone to be cut from the patient. Similarly,
length of the bone resected from the patient may be equal to the
length of the donor graft bone minus the kerf loss. Similarly, the
length of the framed opening may marked by the inner guidance slot
which may define the length of the resected bone to be cut from the
patient.
Because the bone graft to be resected from the donor bone is
generally larger than the resected opening in the patient bone, the
corresponding bone graft dimensions to be cut from the donor may be
demarcated by the outer guidance slots. Thus, the width of the bone
graft to be resected from the donor bone may be defined by the
outer guidance slots. Generally, the outer guidance slots may have
dimensions which account for the saw kerf when cutting the graft
from the donor site. Thus, the outer guidance slots may be sized by
estimating the graft dimensions as the resection length plus kerf
loss, resection width plus kerf loss, and resection thickness plus
kerf loss.
As above, the thickness of the bone to be resected from the patient
is equal to the thickness of the donor bone minus the kerf loss due
to the saw or blade. The corresponding height of the bone to be
resected from the patient may be seen by the height extending from
the contact surface of frame to the inner guidance slot and the
height of the bone to be grafted from the donor may be seen by the
height extending from the contact surface of frame to the outer
guidance slot.
Once the template assembly has been situated and secured against
the region of the bone to be resected, a saw may be initially
inserted along the inner guidance slot and advanced into and
through the bone to a predetermined depth, such as the length of
the template assembly, until the bone has been cut completely over
the width of inner guidance slot. The saw may then be removed or
left in place within the bone. The saw (or an additional saw) may
then be introduced along the inner guidance slot to complete the
cut within the bone to a predetermined depth, such as the depth
defined by the template assembly. Similarly, additional cuts may be
made along the inner guidance slots by the same or additional saws
to result in a completely resected bone segment.
The same or additional saws may then be inserted and guided within
the respective outer guidance slots to cut along the predetermined
paths for resecting a bone section from the donor bone which is
slightly larger than the portion resected from the patient bone but
which still has the same relative dimensions and consistent cuts to
result in a press-fit graft which is consistently sized between
donor and patient.
As the saw or blade is inserted along the guidance slots, the depth
to which the cuts are made may be controlled through a number of
different mechanisms. In one example, the saw may have one or more
markers or visual indicators (e.g., laser markers) placed upon the
surface of the saw to correspond to the desired cutting depth. Such
markers or indicators may be consistent between each guidance slot
or they may be varied depending upon which guidance slot the saw is
inserted within. Alternatively, rather than a marker or visual
indicator, the saw may have a projection or protrusion which
functions as a stop such that when the projection or protrusion
abuts against the guidance slot of the template assembly, then the
desired cutting depth has been reached. By maintaining
predetermined cutting depths along the guidance slots, consistent
resections or grafted bone segments may be maintained between the
donor bone and patient bone with minimal damage to surrounding bone
or tissue.
In addition to the saws or blades having indicators for monitoring
cutting depth, the one or more securement wires, e.g., K-wires,
olive wires, pins, etc., which may be used to secure the template
assembly to the donor and/or patient bone may also define one or
more respective markings or visual indicators along their lengths
such as graduations. The markings may be measured against the
respective insertion hole to determine the insertion depth into the
donor and/or patient bone and/or tissue. By monitoring the
securement wire insertion depth, damage to the underlying bone
and/or tissue may be minimized but may still ensure that an
adequate insertion depth has been achieved to maintain a secure
placement of the template assembly relative to the underlying
bone.
In one example of use, the portion of bone to be resected from the
patient may be cut and removed first and the same template may then
be used to resect the bone graft from the donor bone.
Alternatively, the donor graft may be resected first and the
portion of bone to be resected from the patient may be then
resected. In yet another alternative, both the bone of the patient
and the bone of the donor may be resected simultaneously by
utilizing multiple template assemblies having identical
dimensions.
The portion of the bone to be repaired in the patient may be first
identified and the template assembly may then be placed into
contact against the patient bone such that the framed opening of
template assembly surrounds the portion of the patient resected
bone to be repaired. With the template assembly initially held in
place against the surface of the patient bone, one or more
securement wires may be inserted through the template assembly,
e.g., through the openings defined along the cross-member, while
monitoring their insertion depth to hold the template in place
relative to the bone surface. Because the damaged patient resected
bone bounded by the framed opening is to be removed from the
patient bone, the one or more securement wires may be inserted
specifically into the patient resected bone through the
cross-member such that the surrounding bone may remain undamaged or
untouched by the securement wires.
With the template assembly secured in place, the saw may be
inserted through inner guidance slot and the bottom cut may be made
into the bone first while monitoring and/or measuring the cutting
depth via the optional graduations along the saw. The saw may be
optionally left in place within the bone and the remaining cuts may
then be made. Alternatively, the same saw and/or additional saws
may be then inserted along the side inner guidance slots to make
the cuts into the patient bone while monitoring and/or measuring
the cutting depth. The same saw or additional saws may then be used
to make the final cut along the distal inner guidance slot. The
patient resected bone may be removed by tensioning the handle
and/or securement wires to leave the resected channel for grafting.
In other variations, the order of the cuts into the bone may be
altered as suitable or desired. For instance, the initial cut into
the bottom of the patient resected bone may be followed by cuts
into the distal end of the bone followed by subsequent cuts along
the sides of the bone. In yet other alternatives, an initial cut
may be made along the distal end of the patient resected bone
followed by cuts along the bottom and/or sides of the bone.
The patient resected bone may be removed from the template assembly
which may then be placed into contact against the donor bone such
that the framed opening of the template bounds a region of the
donor resected bone similar to the patient resected bone. With the
handle used to hold the template in place, one or more securement
wires may then be passed through the openings defined along the
supporting flanges which extend exteriorly of the framed opening
and into the underlying donor bone while optionally measuring the
insertion depth of the securement wires. Because the donor resected
bone is to be removed from the donor bone and grafted into the
resected channel defined by the patient resected bone, the one or
more securement wires may be inserted through the supporting
flanges to secure the template assembly relative to the donor bone.
This ensures that the graft donor resected bone remains undamaged
by any additional openings which may otherwise be created by the
insertion of securement wires.
In yet another variation of the template assembly, a template may
utilize a first template for placement upon a bone of the donor and
an additional second template for placement upon a bone of the
patient. A common guide housing may be utilized between the two
different templates to maintain consistency between the resected
bone from the patient and the resected bone from the donor for
grafting into the patient bone.
Generally, such a template assembly may comprise a first template
for placement upon a bone of a donor, where the first template
comprises a first frame which defines an open area of tissue upon
the bone of the donor, a second template for placement upon a bone
of a patient, where the second template comprises a second frame
which defines an open area of tissue upon the bone of the patient,
and a guide housing which defines a receiving channel for tissue,
where the guide housing is further configured to engage the open
area of the first template and the open area of the second
template.
One example for using the template assembly may generally comprise
securing the first template upon a first tissue region to be
resected, where the first template defines an open area of the
first tissue to be resected, engaging the guide housing along the
first template over the open area of the first tissue, resecting
the first tissue by cutting along first guidance slots defined
between the first template and the guide housing, engaging the
second template upon a second tissue region to be resected, where
the second template defines an open area of the second tissue to be
resected, engaging the guide housing along the second template over
the open area of the second tissue, and resecting the second tissue
by cutting along second guidance slots defined between the second
template and the guide housing.
An internal saw guide assembly may utilize a guide housing between
the bone of the patient and the bone of the donor to maintain
cutting consistency. The guide housing may form a housing which is
open along the portion which contacts the surface of the bone (both
donor and patient) to be resected. The guide housing may have a
handle which extends from the housing and may further define
channels along the sides and bottom portion of the housing for
guiding and/or receiving one or more saws. The top of the guide
housing may define one or more openings through which one or more
corresponding securement wires or pins may be inserted for securing
the guide housing to the underlying bone.
The guide housing may be engaged with or inserted along a donor
template as well as a corresponding patient template, as described
below. The donor template may define one or more openings through
which securement wires or pins may be inserted for securing the
template to the donor bone. The donor template may accordingly
define a contact surface for placement along or upon the underlying
bone as a well as a curved template portion to facilitate
conformance against the bone surface.
In use, a patient template which defines a curved template portion
and a contact surface for conformance against the underlying
patient bone may be placed upon a region of the patient bone such
that the framed opening bounds the portion of the patient resected
bone which is damaged and which is to be replaced by a graft. The
patient template may be maintained in place against the patient
bone by the handle attached to the template and/or by one or more
securement wires which may be inserted through the template and
into the underlying bone. A first saw may be inserted through a saw
guide defined along the template to a predetermined depth. Then the
guide housing may be advanced along and within the framed opening
such that the guide housing is fully engaged within the template.
The guide housing may be secured and maintained against the patient
template as well as the patient bone by inserting one or more
securement wires or pins through the openings defined through the
guide housing. Moreover, the securement wires or pins may be
secured directly to the patient respected bone to be removed and
replaced by the graft.
With the guide housing secured within the patient template and
against the patient resected bone, a second saw may be inserted
between the patient template and the distal portion of the guide
housing. The saw may be inserted to a predetermined depth, e.g., by
one or more graduations defined along the saw body, or until the
distal cutting edge comes into contact against the first saw which
may be left in place within the bone to define a stop or boundary
to prevent the further advancement of the saw into the underlying
patient bone. The remaining saws may be advanced along the sides of
the guide housing and within the patient template to completely
resect the patient resected bone within the guide housing.
With the patient bone resected, the donor bone may also be resected
in a similar manner but with a second donor template which defines
an opening which corresponds in size with the patient template
framed opening. The donor template may similarly define a contact
surface for placement against the donor bone such that the opening
of the donor template frames the donor resected bone to be grafted.
Hence, the framed donor resected bone may be consistent in size
with the channel defined by the patient resected bone in the
patient bone. The donor template similarly defines one or more
openings through which the securement wires or pins may be inserted
away from the donor resected bone to maintain the integrity of the
graft. The donor template may define a receiving channel along the
template for receiving the guide housing in a consistent
orientation. Hence, the same guide housing used to create the
patient resected bone may be advanced into a sliding engagement
optionally through the receiving channel upon the donor bone.
As with resection of the patient bone, once the guide housing is
secured along the donor template, the first saw may be advanced
along the bottom portion of the donor resected bone. The additional
saws may be advanced into contact against the first saw to form the
distal end of the donor resected bone and the remaining saws may be
advanced along the respective sides of the guide housing between
the donor template to completely resect the donor resected bone
within the guide housing. The donor resected bone may then be
removed from the donor bone and grafted into the channel formed by
the patient resected bone.
In yet another variation of a resection template, a guide template
may be configured to be placed against an anterior portion of a
bone to be resected. The anterior guide template may be configured
to form a bone receiving channel defined by contact surfaces formed
along template walls extending partially from a transversely
oriented guide surface. A handle may extend from the anterior guide
template to facilitate handling of the template and the guide
surface may define one or more openings for the passage of
securement wires or pins into the underlying bone to be resected.
The guide surface may also define one or more guidance slots which
may be aligned in a transverse orientation such that one or more
corresponding saws may be inserted into the respective slots to cut
the bone contained within the bone receiving channel. Other
variations of an anterior resection template may omit the bone
receiving channel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B show alternate perspective views of one variation
of an allograft template.
FIGS. 2A to 2D show respective top, side, end, and perspective
views of the template of FIG. 1A.
FIGS. 3A and 3B show top and end views of the template to
illustrate the inner and outer guidance slots which are adjacent
and parallel to one another.
FIG. 4A shows a perspective view of a template with saws inserted
through each of the inner guidance slots.
FIG. 4B shows a perspective view of a template with saws inserted
through each of the outer guidance slots.
FIG. 5 shows a perspective view of one variation of a graduated saw
having indicators for determining a cutting depth.
FIGS. 6A and 6B show perspective and side views of another
variation of a saw having a tapered cutting portion.
FIG. 7 shows a perspective view of a template having graduated
securement pins or wires for determining an insertion depth into
the bone or tissue.
FIGS. 8A and 8B show perspective views of a template having both
saws and securement pins or wires graduated and placed upon a bone
for resection.
FIGS. 9A to 9D show views of an alternative template assembly
having guidance slots, e.g., outer guidance slots, angled for
forming tapered surfaces in the underlying resected bone.
FIGS. 10A and 10B show perspective views illustrating a template
placed upon a bone to be resected from a patient where portion of
bone to be removed may be secured.
FIGS. 10C and 10D show perspective views illustrating the patient
bone to be resected being sawed along the inner guidance slots.
FIGS. 11A and 11B show perspective views illustrating the template
secured to the bone of a donor outside of the portion to be
resected.
FIGS. 11C and 11D show perspective views illustrating the donor
bone to be resected being sawed along the outer guidance slots.
FIG. 12 shows a perspective view of another variation of an
allograft template having an adjustable frame assembly.
FIGS. 13A and 13B show perspective views of the adjustable
allograft template illustrating the frame assembly adjusted into
different configurations.
FIGS. 14A and 14B show perspective views illustrating how the
adjustable allograft template may be adjusted to vary the template
position relative to the underlying bone.
FIG. 15 shows a perspective view of another variation of an
allograft template.
FIGS. 16A and 16B show perspective views illustrating a patient
template secured to the bone of the patient.
FIGS. 16C and 16D show perspective views illustrating a guide
housing being secured along the patient template and the patient
bone sawed accordingly.
FIGS. 17A and 17B show side and bottom views of a variation of a
guide housing used for guiding the saw blades.
FIGS. 18A and 18B show perspective views of a donor template
secured to the bone of the donor and the guide housing secured
along the template.
FIGS. 18C and 18D show perspective views of the donor bone being
resected by the saw blades.
FIGS. 19A to 19C show various perspective views of another
variation of an allograft template which allows for bone resection
along an anterior or side portion of the bone.
FIGS. 20A and 20B show perspective and end views of the allograft
template.
FIGS. 21A and 21B show perspective and end views of another
variation of an allograft template.
FIGS. 22A and 22B show perspective and end views of yet another
variation of an allograft template.
DETAILED DESCRIPTION OF THE INVENTION
An allograft template may be used as a cutting jig which allows for
en bloc resection and grafting of tissue, namely portions of bone,
between a donor and a patient. The template may be sized in various
configurations such that the template may be used for resection and
grafting along various regions of the body. Hence, while one
particular application for the template may be for resection and
grafting to correct for osteochondral lesions along the talus bone,
the template may be used in various alternative orthopedic
procedures.
The allograft template may facilitate guidance of the saw to allow
for resection of a donor graft in a size which is slightly larger
than the portion of bone to be resected from the patient bone.
Because the same template may be used between the donor and the
patient, the cuts may be maintained in a consistent manner between
the resection sites. Moreover, by accounting for kerf losses in the
bone due to the saw cuts, the resection sizes may be offset
accordingly by the template. The resulting donor graft may be
implanted in the patient resection site resulting in a press-fit
which backfills the patient resection site and ensures a secure
graft. Hence, the allograft template reduces errors in forming a
resection site in the bone of the patient and further reduces
errors (e.g., errors resulting from thickness of the blade,
measurement errors, cutting errors, etc.) in the forming and
extraction of the graft from the bone of the donor.
FIGS. 1A and 1B show alternate perspective views of one variation
of an allograft template assembly 10 which generally comprises a
first portion of a frame 12A which may lie along a first plane and
a second curved portion 12B which may extend or curve in an arcuate
manner away from the frame 12A along a second plane. The frame 12A
and curved portion 12B may together form a framed opening 18 which
defines the border or framed boundary of the bone portion to be
either grafted and/or resected. Moreover, the frame 12A and curved
portion 12B may define one or more frame guidance slots 30 and
guidance slots 32 along the template assembly 10 for defining the
tissue area to be cut and for guiding the saw and/or blade along
the tissue, as described in further detail below.
The template assembly 10 may also define a contact surface 14 for
placement against the surface of the bone or tissue to be grafted
and/or resected. The contact surface 14 may simply follow the frame
12A and curved portion 12B or the contact surface 14 may be
specially contoured to conform to any number of tissue regions such
as the superior region of a talus bone. Additionally, the frame 12A
and/or curved portion 12B may incorporate a cross member 16
extending between the frame 12A members for providing structural
support and stability and also for optionally providing one or more
cross member openings 28 through which pins or wires may be passed
for securement to the underlying tissue or bone, such as the bone
to be resected from a patient. To facilitate handling of the
template assembly 10 during a grafting and/or resection procedure,
one or more handles 34 may be attached, for instance, along the
cross member 16 to extend from the template assembly 10. Handles
may be positioned along other sections of the template assembly 10
if so desired.
One or more supporting flanges 20, 22 may also be optionally
integrated to extend outwardly along one or both sides of the frame
12A and/or curved portion 12B. These supporting flanges 20, 22 may
define one or more flange openings 24, 26 defined at various angles
therethrough. Pins or wires may be passed through these flange
openings 24, 26 for securement to the underlying tissue or bone,
such as the bone of the donor at regions adjacent to the resected
bone.
FIGS. 2A to 2D show respective top, side, end, and perspective
views of the template assembly 10 with the handle removed for
clarity. Moreover, the frame 12A and curved portion 12B may be seen
with an inner guidance slot 40A, 40B, 40C defined along the length
of frame 12A and part of curved portion 12B. An additional outer
guidance slot 42A, 42B, 42C may also be seen along the length of
frame 12A and part of curved portion 12B in parallel with the inner
guidance slot 40A, 40B, 40C. With the inner and outer guidance
slots defined parallel to one another along frame 12A and curved
portion 12B, the saw or blades may be inserted through or along a
respective guidance slot such that the saw or blade become
transversely oriented relative to the inner guidance slot 44 and
outer guidance slot 46 of guidance slot 32. The saw or blade
inserted along the inner and outer guidance slots 44, 46 may be
oriented to be parallel with the handle and/or transverse to the
cuts made by the saw or blade being inserted through the inner
guidance slots 40A, 40B, 40C or the outer guidance slots 42A, 42B,
42C.
While the size of template assembly 10 may be varied according to
the size of the bone or tissue to be resected as well as the shape
of the anatomy within the body, the template assembly 10 may be
varied in dimension. For illustrative purposes, the variation shown
may generally have a width of about 0.90 inches and a height of
about 0.75 inches. The supporting flanges 20, 22 may also have a
width of about 0.19 inches while the inner guidance slots 40A, 40B,
40C and the outer guidance slots 42A, 42B, 42C may be sized to have
a width to accommodate any number of saws or blades, e.g., 0.02
inches. Typical surgical saw blades (e.g., available from
Synvasive.RTM., Stryker.RTM., etc.) may range in thickness from,
e.g., 0.005, 0.010, 0.015 inches or more; hence, a guidance slot
width of 0.02 inches is sufficient to accommodate many surgical
saws although the slot width may be sized to be greater if needed
or desired, as well as the angle of control the template places on
the blade may be varied. For example a 2.5 degree angle on the
outer slot can help create a tighter press fit, as described in
further detail herein. The remaining inner and outer guidance slots
44, 46 may also have width, e.g., ranging from 0.02 to 0.04
inches.
In use, the template assembly 10 may be used to resect a portion of
bone from the bone of the donor which is slightly larger than the
corresponding resected opening in the bone of the patient. Hence,
the resulting resected bone segment from the donor may result in a
graft which can be press-fit into the patient's bone. By accounting
for the kerf loss in the bone or tissue typically due to the width
of the saw or blade passing through bone or tissue, the width of
the resected bone portion may be sized in a consistent and
repeatable manner. As shown in the top view of template assembly 10
in FIG. 3A, the opposed inner guidance slots may be separated from
one another to have a width of the patient's bone plus the kerf
loss to be equal to the width of the donor's bone minus the kerf
loss. Hence, the inner guidance slots 40B, 40C may define the width
of the resected bone PW to be cut from the patient. Similarly,
length of the bone resected from the patient may be equal to the
length of the donor graft bone minus the kerf loss. As shown in
FIG. 3A, the length of the framed opening 18 may marked by the
inner guidance slot 40A which may define the length of the resected
bone PL to be cut from the patient.
Because the bone graft to be resected from the donor bone is
generally larger than the resected opening in the patient bone, the
corresponding bone graft dimensions to be cut from the donor may be
demarcated by the outer guidance slots 42A, 42B, 42C. Thus, the
width of the bone graft DW to be resected from the donor bone may
be defined by the guidance slots 42B, 42C. Similarly, the length of
the bone graft DL to be resected from the donor bone may be defined
by the guidance slot 42A. Generally, the outer guidance slots 42A,
42B, 42C may have dimensions which account for the saw kerf when
cutting the graft from the donor site. Thus, the outer guidance
slots may be sized by estimating the graft dimensions as the
resection length plus kerf loss, resection width plus kerf loss,
and resection thickness plus kerf loss.
Likewise, the height of the bone to be resected may be demarcated
by the guidance slots as shown in the end view of FIG. 3B. As
above, the thickness of the bone to be resected from the patient is
equal to the thickness of the donor bone minus the kerf loss due to
the saw or blade. The corresponding height of the bone to be
resected from the patient may be seen by the height PH extending
from the contact surface of frame 12A to the inner guidance slot 44
and the height of the bone to be grafted from the donor may be seen
by the height DH extending from the contact surface of frame 12A to
the outer guidance slot 46.
FIGS. 4A and 4B illustrate perspective views of the frame assembly
10 with multiple saws or blades inserted within their respective
guidance channels to show the saw and template assembly
interaction. The example shown in FIG. 4A illustrates how the
template assembly 10 may be used to resect a portion of bone to be
replaced from a patient. Although multiple saws are shown for
illustrative purposes, a single saw or blade may be used to
sequentially form the cuts defined by each slot. Alternatively,
multiple blades may be used simultaneously along one or more
guidance slots to facilitate the bone resection.
In either case, once the template assembly 10 has been situated and
secured against the region of the bone to be resected (in this
example the bone of the patient), a saw 50D may be initially
inserted along the inner guidance slot 44 and advanced into and
through the bone to a predetermined depth, such as the length of
the template assembly 10, until the bone has been cut completely
over the width of inner guidance slot 44. The saw 50D may then be
removed or left in place within the bone. The saw 50D (or an
additional saw 50A) may then be introduced along the inner guidance
slot 40A to complete the cut within the bone to a predetermined
depth, such as the depth defined by the template assembly 10.
Similarly, additional cuts may be made along the inner guidance
slots 40B, 40C by the same or additional saws 50B, 50C to result in
a completely resected bone segment.
The same template 10 is also shown in the perspective view of FIG.
4B where the template assembly 10 may then be placed or otherwise
secured to the bone of a donor. The same or additional saws 50A,
50B, 50C, 50D may then be inserted and guided within the respective
outer guidance slots 42A, 42B, 42C, 46 to cut along the
predetermined paths for resecting a bone section from the donor
bone which is slightly larger than the portion resected from the
patient bone but which still has the same relative dimensions and
consistent cuts to result in a press-fit graft which is
consistently sized between donor and patient.
As the saw or blade is inserted along the guidance slots, the depth
to which the cuts are made may be controlled through a number of
different mechanisms. In one example, the saw may have one or more
markers or visual indicators (e.g., laser markers) placed upon the
surface of the saw to correspond to the desired cutting depth. Such
markers or indicators may be consistent between each guidance slot
or they may be varied depending upon which guidance slot the saw is
inserted within. Alternatively, rather than a marker or visual
indicator, the saw may have a projection or protrusion which
functions as a stop such that when the projection or protrusion
abuts against the guidance slot of the template assembly 10, then
the desired cutting depth has been reached. By maintaining
predetermined cutting depths along the guidance slots, consistent
resections or grafted bone segments may be maintained between the
donor bone and patient bone with minimal damage to surrounding bone
or tissue.
FIG. 5 illustrates an example of a surgical saw 50A having a saw
body 52 terminating in a distal cutting edge 54 and having a handle
portion 56 of the proximal edge. The body 52 may define one or more
graduations 58 along the length of the body 52 such that the
cutting depth may be measured during a resection procedure by
comparing the indicated depth against the guidance slot of the
template assembly 10. FIGS. 6A and 6B show perspective and side
views of an alternative saw 60 having a saw body 62 and a tapered
portion 66 which tapers into a gradually thicker section relative
to the saw body 62 and terminates in a cutting edge 64. Saw body 62
may also define one or more graduations along the body 62 for
gauging the cutting depth.
In addition to the saws or blades having indicators for monitoring
cutting depth, the one or more securement wires 70, 74, e.g.,
K-wires, olive wires, pins, etc., which may be used to secure the
template assembly 10 to the donor and/or patient bone may also
define one or more respective markings or visual indicators along
their lengths such as graduations 72, 76 as shown in the
perspective view of FIG. 7. The markings may be measured against
the respective insertion hole to determine the insertion depth into
the donor and/or patient bone and/or tissue. By monitoring the
securement wire 70, 74 insertion depth, damage to the underlying
bone and/or tissue may be minimized but may still ensure that an
adequate insertion depth has been achieved to maintain a secure
placement of the template assembly 10 relative to the underlying
bone.
FIG. 8A shows a perspective view of a template assembly having one
or more saws 50A, 50B, 50D inserted through a respective guidance
slot and securement wires 70, 74 inserted through respective
securement openings 24, 28. FIG. 8B shows a perspective view of the
template assembly 10 placed against the bone BN. The template
assembly 10 may be seen secured to the bone by the insertion of the
securement wire 70 placed through opening 28 defined along
cross-member 16 to prevent or inhibit movement of the template 10
relative to the bone BN during the resection procedure. The
insertion depth of the securement wire 70 may be gauged by the
graduations 72 marked against the cross-member 16 to ensure that
the securement wire 70 is sufficiently inserted into the underlying
bone to be resected RS but not deeply enough to damage bone or
tissue beyond the resected portion RS.
With the template assembly 10 secured accordingly, the saw 50D may
be inserted through the appropriate guidance slot and the same or
additional saws 50A may be inserted through its respective guidance
slot to further cut around the bone. As shown, with the graduations
58 marked along the body of saw 50A, the cutting depth may be
monitored and measured by the degree to which the saw 50A is cut
into the bone relative to the guidance slot.
In one example of use, the portion of bone to be resected from the
patient may be cut and removed first and the same template may then
be used to resect the bone graft from the donor bone.
Alternatively, the donor graft may be resected first and the
portion of bone to be resected from the patient may be then
resected. In yet another alternative, both the bone of the patient
and the bone of the donor may be resected simultaneously by
utilizing multiple template assemblies having identical
dimensions.
In yet another variation of the template assembly, the outer guide
73A along the frame 12A and/or curved portion 12B may be angled
relative to a normal axis L defined by the framed opening 18, as
shown in the cross-sectional side view of FIG. 9A. While the inner
guide 71A may remain relatively parallel with the normal axis L,
the outer guide 73A may be angled slightly, e.g., forming an angle
of 2.5 degrees relative to the normal axis L and/or inner guide
71A, such that the angle tapers away from the framed opening 18.
The degree to which the guidance slots are angled may of course be
varied depending upon the degree of taper to be formed along the
resected bone and/or channel.
An additional chamfer 75 may be formed along the entry of the outer
guide 73A to facilitate the insertion of the saw into the guide. By
angling the outer guide 73A in such a manner relative to the inner
guide 71A, the saw may be correspondingly guided at an angle along
the guide 73A such that the bone graft resected from the donor bone
DBN may be formed with tapered sides which may help to form a
tighter press-fit graft when implanted into the patient.
In other variations, the inner guide may be angled relative to the
normal axis L or both the inner 71A and outer 73A guides may be
angled relative to one another and/or relative to the normal axis L
of the framed opening 18. In either case, the use of angled
guidance slots may be utilized in combination with any of the
embodiments described herein as practicable.
FIG. 9B shows a perspective view of the template assembly with saws
50A and 50A' inserted through respective inner 71A and outer 73A
guidance slots to illustrate how the saw 50A' inserted through
outer guidance slot 73A may form a tapered cut relative to the cut
formed by saw 50A inserted through inner guidance slot 71A when
inserted into the underlying bone. FIG. 9C shows a side view also
illustrating the angled taper formed by the resulting cuts into the
underlying bone.
FIG. 9D shows an end view illustrating how the outer slots 79B, 79C
defined along the sides of the framed opening 18 may also be formed
at an angle relative to the normal axis L and respective inner
slots 77B, 77C. The saws 50B and 50C inserted through respective
inner guidance slots 77B and 77C may be seen formed relatively
parallel to form straight, parallel cuts into the underlying
patient bone. In contrast, the saws 50B' and 50C' are illustrated
inserted through respective outer guidance slots 79B and 79C at an
angle, e.g., 2.5 degrees, relative to the inner guidance slots to
form angled cuts into the underlying donor bone such that the
resected graft may be formed with tapered sides for the press-fit
implantation into the patient. Any of the template assemblies may
be formed to have every resected side tapered. Alternatively, one
or more sides of the resected graft may be selectively formed with
a taper such that only one side is formed with the taper or two or
more sides may be formed with the taper.
As shown in FIG. 10A, an example is illustrated where the bone of
the patient P may be resected first. The portion of the bone to be
repaired may be first identified and the template assembly 10 may
then be placed into contact against the patient bone PBN such that
the framed opening 18 of template assembly 10 surrounds the portion
of the patient resected bone PRS to be repaired. With the template
assembly 10 initially held in place against the surface of the
patient bone PBN, e.g., via handle 34, one or more securement wires
70, 74 may be inserted through the template assembly 10, e.g.,
through the openings defined along cross-member 16, while
monitoring their insertion depth to hold the template 10 in place
relative to the bone surface, as shown in FIG. 10B. Because the
damaged patient resected bone PRS bounded by framed opening 18 is
to be removed from the patient bone PBN, the one or more securement
wires 70, 74 may be inserted specifically into the patient resected
bone PRS through cross-member 16 such that the surrounding bone may
remain undamaged or untouched by the securement wires.
With the template assembly secured in place, the saw 50D may be
inserted through inner guidance slot 44, as shown in FIG. 10C, and
the bottom cut may be made into the bone first while monitoring
and/or measuring the cutting depth via the optional graduations
along the saw 50D. The saw 50D may be optionally left in place
within the bone and the remaining cuts may then be made.
Alternatively, the same saw 50D and/or additional saws, e.g., saws
50A, 50B, 50C, may be then inserted along the side inner guidance
slots 40B, 40C to make the cuts into the patient bone PBN while
monitoring and/or measuring the cutting depth. The same saw or
additional saws may then be used to make the final cut along the
distal inner guidance slot 40A, as shown in FIG. 10D. The patient
resected bone PRS may be removed by tensioning the handle 34 and/or
securement wires 70, 74 to leave the resected channel for grafting.
In other variations, the order of the cuts into the bone may be
altered as suitable or desired. For instance, the initial cut into
the bottom of the patient resected bone PRS may be followed by cuts
into the distal end of the bone followed by subsequent cuts along
the sides of the bone. In yet other alternatives, an initial cut
may be made along the distal end of the patient resected bone PRS
followed by cuts along the bottom and/or sides of the bone.
The patient resected bone PRS may be removed from the template
assembly 10 which may then be placed into contact against the donor
bone DBN from a donor D such that the framed opening 18 of template
10 bounds a region of the donor resected bone DRS, as shown in FIG.
11A, similar to the patient resected bone PRS. With the handle 34
used to hold the template 10 in place, one or more securement wires
70, 74 may then be passed through the openings 24, 26 defined along
the supporting flanges 20, 22 which extend exteriorly of the framed
opening 18 and into the underlying donor bone DBN while optionally
measuring the insertion depth of the securement wires 70, 74, as
shown in FIG. 11B. Because the donor resected bone DRS is to be
removed from the donor bone DBN and grafted into the resected
channel defined by the patient resected bone PRS, the one or more
securement wires 70, 74 may be inserted through the supporting
flanges 20, 22 to secure the template assembly 10 relative to the
donor bone DBN. This ensures that the graft donor resected bone DRS
remains undamaged by any additional openings which may otherwise be
created by the insertion of securement wires.
As illustrated in FIG. 11C, the bottom of the donor resected bone
DBN may be cut by the insertion of saw 50D in a manner similar to
the cutting of the patient resected bone PBN. However, the saw 50D
may be inserted into and through the outer guidance slot 46 rather
than the inner guidance slot 44. The depth of the cut may be
monitored and/or measured by the graduations defined along the saw
body, as previously described. The saw 50D or additional saws may
then be used to form the cuts along the sides of the donor resected
bone DBN by inserting the saws along the outer guidance slots 42B,
42C and the distal cut may also be made by inserting the saw along
the outer guidance slot 42A, as shown in FIG. 11D. Once fully cut,
the template assembly 10 may be removed from the donor bone DBN and
the donor resected bone DBN may then be removed from the donor bone
DBN and grafted into a press-fit into the channel defined by the
patient resected bone PBN. As described above with respect to the
cutting of the patient resected bone PBN, the donor resected bone
DBN may be cut in differing order in alternative variations.
To provide for further flexibility in accommodating various
anatomies and variances between patients and/or grafts, an
allograft template assembly may be configured to have an adjustable
medial offset which can be contoured or otherwise adjusted, e.g.,
to a talus dome or other transplate surface. Another variation of
template is shown in the perspective view of FIG. 12 which
illustrates an allograft template assembly 91 which is configured
similarly to other variations described. In this particular
embodiment, the template assembly 91 may incorporate a frame
assembly 93A and curved portion 93B which is slidably adjustable
relative to the rest of the assembly.
The frame assembly 93A may translate proximally or distally along
guides 95A, 95B along respective channels 97A, 97B in-between
supporting flanges 20, 22. The variation shown in FIG. 12
illustrates the frame assembly 93A aligned at a nominal position
relative to the assembly such that the surfaces remain flush as in
the previous variations. However, FIGS. 13A and 13B illustrate how
the frame assembly 93A may be translated to various depths. FIG.
13A shows a perspective view of the frame assembly 93A advanced
proximally relative to the assembly such that the amount of the
patient bone or graft bone may be reduced in depth during a
resection procedure. As shown, as the frame assembly 93A is
translated, the curved portion 93B may be corresponding translated
as well such that the depth of the resected bone remains
consistent.
FIG. 13B likewise shows a perspective view of the template assembly
but where the frame assembly 93A and curved portion 93B has been
adjusted to a distal position relative to the assembly. In this
case, the depth of the patient bone or graft bone may be increased
correspondingly depending upon the patient anatomy and desired
amount of bone to be resected. To assist in adjusting the depth of
the assembly, indicators or gradations may be defined along the
assembly 91 to facilitate positioning of the adjusted depth.
Alternatively, the depth of the frame assembly 93A and curved
portion 93B may be adjusted directly against the patient bone and
frame assembly 93A may be locked into position to maintain the
consistency with the donor graft as well.
Regardless of the depth of the translated frame assembly 93A and
curved portion 93B, the amount of bone resected from the patient
and graft may be maintained in a consistent manner by locking the
frame assembly 93A and curved portion 93B not only to the
underlying bone but also relative to the assembly 91 as well to
prevent undesired movement during resection. Moreover, regardless
of the positioning of the frame, the resection procedure may be
carried out in the same or similar manner as described herein.
As shown in the perspective view of FIG. 14A, the contact surface
14 is illustrated to show how the depth of the frame assembly 93A
may be adjusted by, e.g., translating the frame assembly 93A along
the direction of the movement 99. Alternatively, the contact
surface 14 may be adjusted to match to a bone topography, e.g.,
obtained through a CT scan, by varying the frame assembly 93A
positioning relative to the assembly 91 and locking the position of
the frame assembly 93A.
FIG. 14B shows a perspective view of how the adjustable template
assembly 91 may be positioned upon a region of the bone BN to be
resected. Once the frame assembly has been suitably adjusted, it
may also be stabilized on the bone surface with, e.g., one or more
K-wires, as previously described.
In yet another variation of the template assembly, FIG. 15 shows a
template which may utilize a template for placement upon a bone of
the donor and an additional template for placement upon a bone of
the patient. A common guide housing may be utilized between the two
different templates to maintain consistency between the resected
bone from the patient and the resected bone from the donor for
grafting into the patient bone.
As shown in the perspective view of FIG. 15, an internal saw guide
assembly 80 may be seen which may utilize a guide housing 82
between the bone of the patient and the bone of the donor to
maintain cutting consistency. The guide housing 82 may form a
housing which is open along the portion which contacts the surface
of the bone (both donor and patient) to be resected. The guide
housing 82 may have a handle 84 which extends from the housing 82
and may further define channels along the sides and bottom portion
of the housing for guiding and/or receiving one or more saws 86A,
86B, 86C, 86D. The top of the guide housing 82 may define one or
more openings 88 through which one or more corresponding securement
wires or pins 90, as above, may be inserted for securing the guide
housing 82 to the underlying bone.
The guide housing 82 may be engaged with or inserted along a donor
template 92, as shown, as well as a corresponding patient template,
as described below. The donor template 92 may define one or more
openings 94, 96 through which securement wires or pins may be
inserted for securing the template 92 to the donor bone. The donor
template 92 may accordingly define a contact surface 98 for
placement along or upon the underlying bone as a well as a curved
template portion 100 to facilitate conformance against the bone
surface. A handle 102 may also extend from the donor template 92 to
facilitate handling of the assembly.
In use, a patient template 110 which defines a curved template
portion 112 and a contact surface 116 for conformance against the
underlying patient bone PBN may be placed upon a region of the
patient bone PBN such that the framed opening 118 bounds the
portion of the patient resected bone PRS which is damaged and which
is to be replaced by a graft, as shown in the perspective view of
FIG. 16A. The patient template 110 may be maintained in place
against the patient bone PBN by the handle 120 attached to the
template 110 and/or by one or more securement wires which may be
inserted through the template 110 and into the underlying bone, as
described previously. A first saw 86A may be inserted through a saw
guide 114 defined along the template 110 to a predetermined depth,
as shown in FIG. 16B. Then the guide housing 82 may be advanced
along and within the framed opening 118 such that the guide housing
82 is fully engaged within the template 110. The guide housing 82
may be secured and maintained against the patient template 110 as
well as the patient bone PBN by inserting one or more securement
wires or pins 90 through the openings 88 defined through the guide
housing 82, as shown in FIG. 16C. As previously described, the
securement wires or pins 90 may be secured directly to the patient
respected bone PRS to be removed and replaced by the graft.
With the guide housing 82 secured within the patient template 110
and against the patient resected bone PRS, a second saw 86D may be
inserted between the patient template 110 and the distal portion of
the guide housing 82, as shown in FIG. 16D. The saw 86D may be
inserted to a predetermined depth, e.g., by one or more graduations
defined along the saw body, or until the distal cutting edge comes
into contact against the first saw 86A which may be left in place
within the bone to define a stop or boundary to prevent the further
advancement of saw 86D into the underlying patient bone PBN. The
remaining saws 86B, 86C may be advanced along the sides of the
guide housing 82 and within patient template 110 to completely
resect the patient resected bone PRS within the guide housing
82.
FIGS. 17A and 17B show side and bottom views of another variation
of the guide housing 82 to illustrate the opening defined by the
housing 82 for contact against the underlying bone. The first saw
86A may be seen advanced along the guide housing 82 to form a
bottom surface of the guide housing 82 as well as to form a
backstop against which the remaining saws may be advanced or guided
along or against to maintain a controlled cutting path through the
bone.
With the patient bone resected, the donor bone may also be resected
in a similar manner but with a second donor template 92 which
defines an opening which corresponds in size with the patient
template framed opening 118. The donor template 92 may similarly
define a contact surface for placement against the donor bone DBN
such that the opening of the donor template 92 frames the donor
resected bone DRS to be grafted, as shown in the perspective view
of FIG. 18A. Hence, the framed donor resected bone DRS may be
consistent in size with the channel defined by the patient resected
bone PRS in the patient bone PBN. The donor template 92 similarly
defines one or more openings 94 through which the securement wires
or pins may be inserted away from the donor resected bone DRS, as
described above, to maintain the integrity of the graft. The donor
template 92 may define a receiving channel 130 along the template
for receiving the guide housing 82 in a consistent orientation, as
shown in FIG. 18B. Hence, the same guide housing 82 used to create
the patient resected bone PRS may be advanced into a sliding
engagement optionally through receiving channel 130 upon the donor
bone DBN.
As with resection of the patient bone PBN, once the guide housing
82 is secured along the donor template 92, the first saw 86A may be
advanced along the bottom portion of the donor resected bone DRS,
as shown in FIG. 18C. The additional saws 86D may be advanced into
contact against the first saw 86A to form the distal end of the
donor resected bone DRS and the remaining saws 86B, 86C may be
advanced along the respective sides of the guide housing 82 between
the donor template 92 to completely resect the donor resected bone
DRS within the guide housing 82, as shown in FIG. 18D. The donor
resected bone DRS may then be removed from the donor bone DBN and
grafted into the channel formed by the patient resected bone
PRS.
In yet another variation of a resection template, FIGS. 19A to 19C
show various perspective views of a guide template 140 which is
configured to be placed against an anterior portion of a bone to be
resected. The anterior guide template 140 may be configured to form
a bone receiving channel 142 defined by contact surfaces 144 formed
along template walls extending partially from a transversely
oriented guide surface 146. A handle 154 may extend from the
anterior guide template 140 to facilitate handling of the template
and the guide surface 146 may define one or more openings 148 for
the passage of securement wires or pins into the underlying bone to
be resected. The guide surface 146 may also define one or more
guidance slots 150, 152 which may be aligned in a transverse
orientation such that one or more corresponding saws 156A, 156B may
be inserted into the respective slots to cut the bone contained
within the bone receiving channel 142.
FIGS. 20A and 20B show alternate perspective and end views of the
anterior guide template 140 to illustrate how the saws 156A, 156B
may be inserted through the respective guidance slots 150, 152 in a
linear manner such that when advanced, the resected bone may be
contained within the bone receiving channel 142 with consistent
cuts along the resected portions. The anterior guide template 140
may be used to resect not only the donor bone but also the patient
bone to ensure that the resected channel in the patient bone is
consistent with the resected bone graft from the donor.
In yet another variation, FIGS. 21A and 21B show perspective and
end views of another anterior template assembly 160 which may be
comprised generally of a first guide section 162 and a second guide
section 164 which are transversely oriented relative to one
another. A handle 168 may extend from the first or second guide
section 162, 164 which may optionally incorporate one or more guide
pins 170, 172. The first and second guide sections 162, 164 may
define parallel inner and outer guidance slots 166 for the
insertion of saws for resecting bone segments from the patient bone
and the donor bone while utilizing the same anterior template
assembly 160. The use of the offset guidance slots 166 may allow
for the creation a donor resected bone which is slightly larger
than the resection channel formed in the patient bone to ensure a
press-fit graft, as described above.
Another variation is shown in the perspective and end views of
FIGS. 22A and 22B of an anterior template assembly 180 similarly
having a first guide section 182 and a transversely oriented second
guide section 184. As with the embodiment of FIGS. 21A and 21B, the
first and second guide sections 182, 184 may define parallel inner
and outer guidance slots 186 for resecting bone segments from both
the patient bone and donor bone.
The applications of the devices and methods discussed above are not
limited to bone resection along the talus bone but may include any
number of other bones or tissue regions in the body. Modification
of the above-described assemblies and methods for carrying out the
invention, combinations between different variations as
practicable, and variations of aspects of the invention that are
obvious to those of skill in the art are intended to be within the
scope of the claims.
* * * * *